The aims of this Core are to: 1. Isolate myocytes from non-failing and failing human ventricular muscle at Temple University School of Medicine and supply these myocytes to investigators involved in the SCOR on Sudden Cardiac Death at Johns Hopkins University School of Medicine. 2. Prepare tissue samples from non-failing and failing human ventricular muscle at Temple University School of Medicine for investigators involved in the SCOR on Sudden Cardiac Death at Johns Hopkins University School of Medicine. 3. Provide primary cultures of human myocytes made at Temple University School of Medicine to investigators involved in the SCOR on Sudden Cardiac Death at Johns Hopkins University School of Medicine for use in gene transfer and cell fusion experiments.